Water-soluble dyestuffs of the triarylmethane series and process of preparing the same



Patented Feb. 18, 1930 UNITED STATES BRUNO FRANCKE AND HANS MOEHRKE,

PATENT OFFICE.

OF HOCHSTONTHEMAIN; GERMANY, AS-

SIGNORS TO GENERAL ANILINE WORKS, INC., NEW YORK, N. Y., A CORPORA- TION OF DELAWARE WATER-SOLUIBI|E DYESTUFFS OF THE TRIARYLMETHANE SERIES AND PROCESS OF PREPARING THE SAME No Drawing. Application filed December 31, 1926,'Serial No. 158,402, and in Germany January 2, 1926.

Our present invention relates to a process of preparing water-soluble dyestuffs of the tri-aryl-methane series capable. of being chromed. We have found that the dyestuffs of the trisiryl-metha-ne series of the general formu a:

' OH OOOH HO- ary1-NH.R

CH COOH wherein R stands for hydrogen or for an alkyl or aryl group, which groups may be substituted, and the R.NH-group is in paraposition to the carbinol, can be converted into water-soluble compounds by treating them with neutral sulfites. The compounds thus obtained can be evaporated without being decomposed. They are, when acidified, retransformed into the primary water-insoluble dyestuffs.

The solubility of the new dyestuffs in water ofl'ers a great technical advance, because it considerably facilitates their application for dyeing purposes, and it is only due to this property that they can be used at all for printing purposes.

The following examples serve to illustrate our invention, but they are not intended to 4 limit it thereto, all parts being by weight:

(1) 51 parts of para-phenyl-para-tolylamine-di-ortho-cresotinic acid-carbinol of the probable formula:

(see the example of German patent specification No. 238.552) are heated, while stirring, with 55 parts of crystallized sodium sulfite and about 1000 parts of water, until the dyestuff is dissolved. The product thus obtained isseparated by filtration from any impurities which may be present and evaporated to dryness. The evaporated colorless product readily dissolves in water; by acidifying it, the original carbinol is re-precipitated. The afterchrorned dyeing of the sulfite compound is violet and has the same properties asthe primary dyestufi".

(2) 55 parts of of the probable formula:

v ,OH om ooorr C a i 011/ coon para-phenyl-para-Gechloro- 2 tolui'dine-di-ortho-cresotinic acid-carbinol are heated, while stirring, with 55 parts of crystallized sodium sulfite and about 1000 parts of water until the dyestuff is dissolved; the mass is then filtered and: evaporated to dryness. The evaporated colorless product, like that described in Example 1, readily dissolves in water and by acidifying it the primary carbinol is re-precipitated. The afterchromed dyeing of the sulfite compound is violet and has the same properties as the original dyestuff.

(3) 61 parts of the dyestufl, of the probable formula:

om coon 011/ cooH preparedfrom 2 molecules of ortho-cresotinic acid and para-chlorbenzaldehyde treated with 1-chloro-2-naphthylamine, are heated, while stirring, with 55 g. of crystallized sodium sulfite and about 1000 parts of water until the dyestufi is dissolved; the mass is then filtered and evaporated to dryness. The

sulfite compound thus obtained behaves entirely'like' the compounds described in Examples 1 and 2. c

(4) 50 parts of the dyestufi, of the probable formula:

OH ooon 0+ Pyridine t on coon prepared by'treating' 2 mol'eculesof orthocresotinic acid and para-chlorbenzaldehyde with pyridine, are heated, while stirring, with 55 parts of crystallized sodium sulfite and about 1000 parts of water until the dyestuff is dissolved the mass is then filtered and evaporated to dryness. Theproperties and the behaviour of the compound thus obtained are also analogous to those described in the preceding examples. The dyeing obtainable by the dyestufl' is greenish-blue.

Weclaim: n 1. The process of preparing water-soluble dyestuffs of the triarylmethane series capable of being chromed which consists in treating a compound of I the general formula r on H CH3 COOH CHa 00011 wherein R stands for hydrogen or for an alkyl or'aryl group, which groups may be substituted, the R.NH-group standing in sulfite.

2. The process of preparing water-soluble dyestuffs ofthe triarylmethane series capable para-position to the carbinol, with a neutral of being chromed which consists in treating 1 mol of a compound of the general formula CH: COOH Hoaryl-NH.R

CH 00H dyestuffs of the triarylmethane series capable of being chromed which consists in treatl ing-a compound of the general formula:

v on em coon HO-CONHR OH 00011 f wherein R stands for hydrogen or alkyl or aryl which groups may be substituted-with a neutral sulfit e.

4. The process of preparing water-soluble :dyestufi's of the triarylmethane series capable of being chromed which consists in treating 1 mol of a compound of the general formula: t

wherein R stands for hydrogen oralkyl or aryl which groups may be substituted, with 2 mols of crystallized sodium sulfite in the presence of water. v

5. The process of preparing water-soluble dyestuflt's of the triarylmethane series capable 0 of'being chromed which consists in treating.

" a compound of the general formula:

on t I cm coon H with a neutral sulfite..- 6. The process of preparing water-soluble dyestufifs of the triarylmethane series capable 0 being chromed which consists in treating 1 mol of a compound of the formula:

' n with 2 mols of crystallized sodium sulfite in the presence of water.

7. As new products, compounds obtaintures.

ing constitution:

coon wherein R stands for hydrogen or alkyl or aryl which groups may be substituted, with neutral sulfites, being soluble in water and. i

not decomposing when evaporated.

9. As a new product, a compound obtaim able by treating the para-phenyl-para-tolylamine di-ortho-cresotimc acid-carbinoh of the constitution: 1

H in the presence of water with 2 mols of crystallized sodium sulfite, beingl colorless, easily soluble in water, and capa 1e of being retransformed. by acidification into the car- 7 binol used as starting material.

In testimony whereof,- we afiix BRUNO FRANCKE. HANS MOEHRKE.

able b treating a compound of the general form 65 our signa 

